When a liquid crystal display device displays images, switching of each frame of image is achieved by scanning of scanning lines.
Since scanning lines are made of metal materials which have resistance, a voltage on a scanning line decreases with increase of a transmission distance. This phenomenon is called a voltage drop. As shown in FIG. 1, with increase of distances from an input end of a gate line to a pixel A, to a pixel B, and to a pixel C, voltage drops increase.
Specifically, an expression of the voltage drop on a gate line in an existing liquid crystal display panel is as follows:
            Δ      ⁢                          ⁢      Vp        =                            C          gs                                      C            gs                    +                      C            lc                    +                      C            s                              *              V        ghl              ,where ΔVp represents a voltage drop value, Cgs represents a capacitance between a gate line and a source/drain of a switching element, Clc represents a liquid crystal capacitance, Cs represents a storage capacitance, and Vghl represents a difference between an ideal input voltage and an actual input voltage.
FIG. 2 schematically shows voltage drops at the pixel A, the pixel B, and the pixel C. With the increase of distances from the pixel A, the pixel B, and the pixel C to the input end of the gate line (i.e., distances from the pixel A, the pixel B, and the pixel C to a scanning signal driving circuit increase), voltage drops increase, i.e., Va<Vb<Vc. In FIG. 2, Va, represents a voltage drop at the pixel A, and ΔVa represents a feedthrough voltage at the pixel A; Vb represents a voltage drop at the pixel B, and ΔVb represents a feedthrough voltage at the pixel B; Vc represents a voltage drop at the pixel C, and ΔVc represents a feedthrough voltage at the pixel C; and Vgh represents an ideal input voltage on the gate line. It is known from the above expression of the voltage drop on a gate line that the presence of ΔVp can cause an image to be relatively bright at a part thereof close to the input end of the gate line and relatively dark at a part thereof far from the input end of the gate line, which affects display uniformity of a panel.